Imaging Modalities of Retinoblastoma

Cat's eyes or also called leukocoria are the appearance of white dot on the black side of the eye (pupil) when exposed to the light, it is a characteristic of retinoblastoma in children.

Retinoblastoma is the most common intraocular (eye) tumor in children with an incidence of 1: 15,000 to 1: 18,000 births and most of the symptoms occur at the age of 2 years. Retinoblastoma can occurs on one eye or both eyes. The main clinical picture found in retinoblastoma patients is leukocoria (white retinal reflex). Other symptoms that can be seen are strabismus, proptosis, red eye and pain due to secondary glaukoma, signs of inflammation, and poor vision. At an advanced stage can be found orbital invasion or the growth of extra -ocular mass. The diagnosis of retinoblastoma is made by anamnesis by asking the past illness history, family history of retinoblastoma and enucleation, physical examination and other examinations. Physical examination can be done by using direct funduscopy for leukocoria. On radiological examination, retinoblastoma is generally characterized by heterogeneous retinal masses with calcifications, necrotic components and increased vascularity on ultrasonographic (USG), computed tomography scan (CT), and magnetic resonance imaging (MRI) examinations.

Ultrasound examination is safe for children because it does not cause radiation (using high frequency sound waves), but the patient should be cooperative during the procedure. Ultrasound can be done without anesthesia and can be done repeatedly. The results of this examination will illustrate the presence of echogenic soft tissue with varying shadows due to calcification and heterogeneity due to necrosis and bleeding. The examination will followed by Doppler ultrasound to identify tumor vascularization. On CT scan, the findings include the mass of the eyeball with increased density with contrast media (on calcified tumor). However, this examination can cause radiation because it uses X-rays. While MRI (using magnetic waves) is modality of choice to determine the pre-treatment tumor stage.

Retinoblastoma can be cured with adequate therapy for tumors confined to the eyeball and no signs of metastasis. The management of retinoblastoma helps maintain the life of the patient and as much as possible maintains eyeball and visual function. The type of treatment given depends on the stage of retinoblastoma, including enucleation, focal therapy such as cryotherapy, laser photocoagulation, hyperthermia, irradiation, and systemic chemotherapy.